Ring expander



' Nov. 3, 1931. J. AMAZER RING EXPANDER Filed June-13, 1929 INVENTOR v JOSEPH MAznn, or NEW YQRK, N. Y.

y QRING v'Exialirmnn Primm fla? finie 1.3

I My invention relates to ringiexpanders, and more particularly'to 'devicesfor'stretclnng or enlargingfnger rings orsimilarly-'shaped articlesg, u .Y uw, w

One'objecti'of my invention is to provide a ring' expanderor stretcherfof simple form y which fisl nevertheless'eifective in operation a-ndfffrofinV Whichan expanded ringmaybe readily.removed.l i y u lAgji'other object of myinventiony istoy provideran v expander capable; ofv accurately ;t`retching .rings to a desired; degree with great xactnesls A. f Y

YStillanother objectof'my. invention is to provide an expander of such form that the .nner periphery of the ringv` Will Aexpand in .inesf'parallel' to the axis thereof, notwith-j itandingfthe"'generally tapered' form of the nandrel upOnfWliich the'ri-ng isexpanded. e e Seine oftheformswhich myinvention may ,akefarefshown the vaocompan'ying drawngs,j,"yvherein'Fig. 1 isa 'view of the device, )'a'lrtially'A vin side elevation' and partially lin rection; Fig. Qis'an end elevational vievvL of he device of'Fig.' 1;-Fig. vSfisja'realry elevai'onal vievvfof the mandrel ofFigcl', showing he" guide vvpins e' for the :mandrel segments Fig. 4is`a'view showing a modification lof 'the' nandrel of Fig. 1i; Figs. 5 and; show a sleeve f the Ytype Whichlmay be .employed With the mandrel' kof Fig. 1;, and *Fig."7 vshows a sleeve lth'eJnanolrel'fjlifigp;QV Y y' Refl rri f: `to`;Figs. 1to13, thedevice con'- ists of a basefforipedestal'f which carries a hambereldblock: Theblock '6` is threaded 'A or connection vvith ajsleeve 7 With which an perating 'screWFS hasf'threaded engagement. `The screvvfShas a perforated enlargement tits outer 'endfforythe 'reception 'of Aa handle by"meansoffvhi`ohit may be turnedrflfflhe nner' endoffuthe screw v8Y is of reduced di-y meter as'sliow'n at 10. Thisreducedportion s'threaded so. that facvap 11 mayv be screwed itoposition thereon. The cap 11 servesl` to etac'hably'connectl a plunger or punch v12 to '1e screwS, the plunger having a flanged lhead BWith fvvhichtheouterflangedendiof the vcap*y l has ola/Hpingelgagement;f -The linger 12's; of apefedxfofmi towed l s outer end"- *A mandrel14is'looselyheldj` axially Each of the segments 15 has 'tracting' the' mandrel.

leas. serial, N'o. 3705.26.

betweenthe block 6 and the inner end of the sleeve?, and has 'a central perforation extending'axi'ally thereof. The perforation is `of the' plunger 12. The mandrel 14 is vcomposed ofsegm'ents 15 Which. are shown as live in number, but,iit may have a greater or less number of segments5 as desired; Themandrelis formed b bar along radial ,lines'as shown'more clearly in" Figs. 2 4and 3, todivideitinto segments.`

i la radiallysexof a bar and thereafter slitting the taperingform and conforms to the taper of y drilling a tapering hole 'tending' flange 17 i vat its base, the'tlanges 'being cut away as indicated at 18 to form wide vslots: for the reception of guidepins 19 that are carried vbythe block 6. These pins hold tliefsegments in properly spaced relation, thus preventing the segments moving together at W certain points and consequent excessive yWidveningoff the slotsalong other lines of division between the segments', rand prevent lrotative movementthereo'f.

It Willbe lseen that 4after the mandrel is divided'into segments by ,theY radial slits referred togth'e edges of such segments can be moved into abutting ,relatiom' thereby vcon- The segments are yieldably held in contracted relation by spring clips or 'collars 21 of lWire-like form.l Y

' It, will vbe seen that themandrel can lbe placed `in the vblock 6, with the pins 19 lying pinthe slot'sjj18iandthe'sleeve yinto place'fin the'bloelj,

peripheryof thev mandrel 14 When in 7 then screwed longitudinally thereof; Inorder that the in-l Qner surfae'eof a ring whichis expanded on' the mandrel Will/'be parallel to the axis of the ring'and the mandrel', Von lines extending lony gitudinally 'offthe mandrel,y the mandrel is jsp'onding to arcertain ring size."

Assuming that the 'screw 8 has beenturned VToontracti()nofthe mandrel segments by the springs 21,`an`d it is desiredtoenlarge .a rima- 'from'.size 4;,"yfor example to size 5`, the ring ded position is kcircularfat all points l back to Withdraw theplunger12 to; permit such that if the screw 8 isturnedto its in? Y ment yat vthe outer end, of the screw in abuty ting engagement'witli the end of the sleevev l()4 through the mandrel is tapered to correspond to the taper'of the plunger12, all portions of is placed on the stepped portiona whereupon the lscrew 8 is turned to force the plunger 12'V Y. i into the mandrel 14:, thereby effecting expan' sion of the mandrel'segments and stretching the ring. The tapering of the plunger' 12 is vnerrnost position, that is, with the enlarge-l v7, or with the capii engaging the base of die size.g Since the passageway or perforation the inner surfaces of the' mandrel segments will be engagedfby the plunger and expansive movement of; the segments will occur onl true radi-al lines.v .The swivel connection between thehead 1 3 oir the plungerandthe screw pre'T vvents turning of the plunger and 'consequent` tendency to `twisting of the mandrel segments. Upon turning back of the screw 18, the manv Y"drfel' sections will'be. permitted temovel inwardl'y'undery the tension of the springs 21,

y,thus Vreleasing'the ring.

Airing expanded t'stepa'will when thev i .mandrel is contracted, belo a size to lit upon the step bjwhich may be'size 5, each suc'- ceeding step being a size larger than the preceding one. course, the. difference in diam- 'eterbetweenthev adjacent steps need not necijessarily vbe equal to a full ring size, but may i be oany desired' fraction. of such size.. Assuming' that the -tsteps on the mandrel are graduatedin'full ringsizes, and it is:

- desired toY expand a ring foronly one-fourth- .114(l7- f @sion of thering.v For a halrpsize increase, thel i of alnll size,theri ng isplafced upon theman- 'drei' andthe screw 8 advanceda distinct num.w ber QiturnS, depending upon theV pitchV ofthe screw threadsto eliect the desired expan-` "'screw wouldbeadvanced double the number 14 oit-Eig. V1`,`biit whose periphery isstraight on axiallines 'instead of being stepped; operation of this mandrel is the same asin the Y 5 o 'caseof Fig, 1, excepftjthat graduation marks'y loi turns that it Vis advanced fora Vone-fourth 'y 'may lbe provided thereon'inst'eadiofthe steps. The, .graduation marks :may be omittedfsince if itf-is desired to enlarge a ring ito apre-1 j determined diameter, it need simply be placedv 'o n'.Y the collapsed mandrel andthe expanding screw Tgiven theVY required number of turns in orderV to eiiect. the necessaryexpansion.V 1

i i As heretofore l sta-ted,. when Vthe screw 8 is turned lto litsinnermostposition, the ring maybe expanded a full jsize, thus auto1nati- Vcally .controlling the expansive `movement of 'l themandrell-fffllowever, if it is desired to en- 15,830,2.f35fv 'number of segments, the vspaces between adl 'jacentsegnients will be quite narrow, owing "mandrel 14, the vring will be expanded a Yfull Y to thesmali expansive movement of the segments at each-stretching operation.v For instance,`if six or more segmentsare employed, the-spaces between the segments willV be only about onetenth millimeter in Width when spread to expanda ringja onefourth size. Ordinarily, this distancewould begso small VVthat there wouldbe'no noticeable .protrusion of theinetal'lrmfthe ring intothe spacesA will'be made of sizesto itover the portion@ 2210i Figyl, and thesleeveof Fig. 7 wil be made to coniornrto the'rnandrelof Fig .4Q :Thesesleeves are placed lon the mandre and. the ringstliennplaced overcthe sleeves Upon' expansionfof the mandrel, the sleeves will yield and will serve to bridge y'the space: Vbetween .segments .and prevent extrusionv o:

metal into( such spaces, thus maintaining th ring trulycircular.'` Even though the sleeve be made oi thin yieldable materialfsuch a celluloidfthey will eiectively Vbridge th- .spaces between the mandrel sections .becaus @i the smallnessfof suchspaces. .Y

`I,claimasiny invention A iA 1;;Aringexpander comprising a base hav cylindrical,.chambered block portior a ,sleeve fitting within and having.v lscrew threaded engagement .with said portion, a

operating. screw .having its Vouter portion i 4screw-tlneaded engagement lwith the interic kof saidy sleeve and protruding therefrom', th -innerjend portion ofsaidscrew .beinglo rf 'duced diameter and y'serew#threaded for th vreception of al scnew 'cap ,a :tapered plunge extending throfuglizthe Vinner.Y end oiffsaid ca and "having iangedliueafdy engaged .tl

captofhnld the plungerv k,assembled rela .tionzftd the'V inner endv of said@y screwfand segmental. mandrelslidably orted by YVsaid block in positiontolbe expanded throng inwaz'rd movement ofthe'screw and plunge g2; A ring expander coinprisingla :base ha1 a Y'cylindrical .fchainberedY -block l portie:

.a -sleevetting within and having screw 1threaded*engage1nent-with. said portion, e

f operating .screw having j itsgl'outer portion, .i screw-threaded "engagementVY withthe int rior of' .'sard Ysleeve and protruding ther ifi-om, rtheinner endportionof said screw b or thevmandrel to a 1,830,235 l e l v 3 ng' of reduced diameter and screwlthreaded or the reception of ascrew cap, a tapered )langer extending through theinner end of `aid cap and having a anged head engaged yjthe cap'to hold `the plunger in assembled `elationto theinner end YOi. said screw, and a egmental mandrel slida'bl'y Supported in poition to be expanded through inward movenent of the screw and plunger. u l

Injtestimony whereof I, the said JOSEPH n IAZEB, have hereunto set my hand. Y

JosYEPHMAzER. 

